Sharpening mounting for disks



July,7, 1942. J. N. FENDER SHARPENING MOUNTING FOR D ISKS Filed June 5,1941 iT/YDEZ? 1 N VENTOR.

,4 rra P/Yzy Patented July 7, 1942 UNITED STATES PATENT oFFIcE'SHARPENING MOUNTING F OR DISKS Joseph N. Fender, Dallas, Tex.

Application June 5, 1941, Serial No. 396,670

9 Claims.

This invention relates to grinding machines and it has particularreference to a machine for sharpening plow disks by grinding.

The foremost objects of the invention are: First, to effect the requiredrotation of the disk solely by its frictional contact with the emerywheel; second, to provide a disk mounting which, by virtue of thefrictional rotation imparted to the disk by the grinding wheel, isoscillated to similarly move the disk at its point of engagement withthe grinding wheel, thereby to produce a curved bevel on the disk;third, to provide a disk mounting capable of adjustment in height toeffect proper correlation between the disk and grinding wheel and tofurther provide a base constructed for ready portability and to allowfor tilting of the entire machine to impose sufficient weight on thedisk in grinding to insure maximum abrading effect of the grindingwheel; and fourth, to provide means for neutralizing the oscillatingeffect of the mounting and at the same time predetermining the degree ofinclination of the mounting toward the grinding wheel in order torelieve the weight imposed on the wheel through the disk and to therebyproduce a true circular edge by grinding off the high places to removeirregularities and nicks in the cutting edge.

Broadly, the invention seeks to provide an inexpensive machine by whichthe cutting edges of plow disks may be renewed efficiently withoutrequiring power of operation other than that required to drive aconventional emery or carborundum wheel, a common fixture of anyreasonably well-equipped shop. Moreover, the invention includes amongits features anattachment to deaden or muffle the penetrating ringproduced by subjecting the disc to the effects of a grinding wheel.

With the foregoing objects as paramount, the invention has other objectsand certain features of accomplishment to become apparent in the courseof the following description, taken with the accompanying drawingwherein:

Figure 1 is a rear perspective view of a disk sharpening mountingconstructed according to the present invention.

Figure 2 is an elevational View of the upper portion of the mounting invertical section.

Figure 3 is a detail View of the underside of the oscillating unit takenon line 3-3 of Figure 2.

Figure 4 is a detail perspective view of the slotted collar, a part ofthe oscillating unit.

Figure 5 is a detail perspective view of the attachment serving the dualfuncticn'of holding screw rod mounting by which vertical adjustment ofthe machine is efiected.

Cutting edges of plow disks have heretofore been renewed in many ways,as by filing, grinding, rolling and beating. In sharpening by filing,unless accomplished by accurate, automatic machines, an irregular edgeis produced resulting in an out-of-round disk and non-uniformity withothers of a gang. Disks sharpened by rolling or beating are invariablyflattened or flared and are therefore thrown out of balance when placedin the soil, thus displacing the strain upward, resulting in possiblebreakage of the cast spool or spindle. Moreover, disks sharpened bythese methods are heated'and the temperature thereof changed renderingit easy for the edges to readily split and curl. The present inventionmakes possible the reconditioning of a disc in a minimum of time,without added cost and insures a true, rounded bevel on the cutting edgethereof without changing the temperature of the steel and further,operation of the machine requires but a minimum of attention.

Continuing with a more detailed description of the drawing, reference isprimarily made to Figure 1, wherein is shown the base [0 constructedporting the disk mounting.

of strap iron shaped into a rectangle or square with radially extendingprojections for stability. Pivoted upon a transverse bolt l2 in the baseIll is the lowermost section l3 of the upright sup- In being thus joinedto the base, the upright may be tilted forwardly and rearwardly withrespect to a grinding wheel 14 which is not a part of this invention andis shown only to illustrate the operative relationship with the disk l5,disposed on the mounting.

The upper and mounting carrying section of the upright is identified byreference numeral l6 and telescopically receives the lower section [3and is secured against displacement from adjusted positions on thesection l3 by means of a sleeve. 18 against displacement.

the disk on the mounting and for silencing the noise attending thegrinding.

Figure 6 is a fragmentary detail View of the pivotal mounting of themachine for tilting, and Figure 7 is a fragmentary detail view of thePassing through the sleeve I8 is a screw rod 2|, the latter beingthreadedly passed through a nut 22 (Figure 2) non-rotatably disposed atthe top of the lowermost upright section [3. A crank 23 is aflixed tothe upper end of the screw rod 2| and by operating this crank it isobvious that the engagement of the screw rod with the threaded nut 22will cause the upper section Hi to be raised and lowered with respect tothe lower section of the upright and that the Weight of the upperassembly will prevent any undue displacement of the respective parts.

The foregoing describes two adjustments, that of tilting the entiremounting on its pivot [2 so that the disk l5 may assume the properangular relation to the grinding Wheel M to produce a bevel a and themeans by which the mounting may be raised and lowered to accommodate thedisk to a grinding Wheel at any height.

In order to produce the prerequisite rounded bevel on the disk, it isnecessary that the latter be oscillated in an arcuate plane so that thepoint of contact between the disk and grinding wheel will be constantlymoved between the inner edge of the bevel to the outer and cutting edgeduring rotation of the disk. This is accomplished by means of a pinion24, mounted on a shaft 25, which meshes with a gear 25 carried by a stubshaft 21. The pinion and gear are disposed in a circular housing 28,filled with a suitable lubricant.

The housing 28 is suspended by a tubular member 29 serving as a sheathfor the shaft. On the upper end of the member 29 there is mounted ahousing 30 containing a bearing 3| embracing shaft 25. An annularshoulder 28a, in the housing 30 rests on the inner race of the bearing3| (Figure 2) while the outer race of the bearing rests in a machinedcavity in a reducer 23a threaded upon the upper end of the tubularmember 29. The inner race rests on a shoulder provided on shaft 25. Adust cap 33a. covers the open lower end of the skirt of the housing 33surrounding the reducer 29a.

Some disks have larger hub openings than others and to accommodatethese, a substantially cone-shaped adapter 3|a is placed over the upperend of shaft 25 and rests on a light coiled spring 3| 2), the lower endof the latter surrounding a Y nut 32a, bearing on the shoulder 28a tolock the housing for common rotation with shaft 25. Disposed on top ofthe housing 39 and embracing the adapter 3|a is a concaved disk 32 ofleather or similar material on which is mounted the disk Iii to besharpened.

The housing 30, the shaft housing 29 and the associated elements justdescribed are suspended by means of diametrically opposed pivot pins 33,each being journaled in bearing apertures provided in upwardly extendingarms 34 and 34a, the lower ends of the latter being bolted or otherwisesecured to either side of a nut or collar 34b mounted stationarily onthe shaft housing 23. The lower ends of arms 34 are connected to a frame35, the latter being pivoted axially at b to the housing |1 disposed atthe top of the upper section N5 of the upright or stand. Braces 36 aidin maintaining rigidity of the frame. The lower ends of these braces areconnected at (Figures 1 and 2) to a depending rod 31 whose upper end,being likewise connected to the pivotal point I) of the frame 35, isalso movable when the frame is moved.

It has been particularly pointed out previously that the power ofrotation of the disk I is obtained from the grinding wheel I4. This isdone by so disposing the disk relative to the grinding wheel that itsrotative axis is slightly offset relative to the plane of rotation ofthe grinding wheel. Of course, the direction of rotation of the disk isdetermined by the position of the disk relative to the wheel, that iswhether the axis of the disk is on one side of the rotative plane of theWheel or the other.

Referring again to the specific means for oscillating the shaft anddisk, it will be observed in Figures 1, 2 and 3 that the stub shaft 21on which the gear 26 is mounted, extends through the housing 28 at thebottom. An arm 38, carrying numerical graduations, is afiixed near oneend to the stub shaft 21, functioning therefore in the nature of acrank. A collar 39 conforms to and is slidable on the arm 38 and has apin 40 connected thereto, to which is pivotally connected one end of anarticulated arm 4|. The opposite end of this arm is pivotally connectedto the lower end of the depending rod 31. A wheel clamp 42 secures theouter end of the arm 4| to the pin 40.

It is apparent therefore in operation that as the disk I5 is rotated bythe grinding Wheel M the shaft 25 will rotate to operate the pinion 24and consequently the enmeshing gear 26. The stub shaft 21 to which thearm 33 is aflixed will cause the latter to revolve, moving the collar ina circular manner. The eccentric motion thus effected is brought aboutby the fact that one end of the arm 4| is constrained against other thanpivotal movement on a horizontal plane and articulated motion, permittedby the pivoted joints of which the arm is composed. These movements areprovided in order that the arm 4| may follow the circular movements ofthe arm 28, the radius of which is determined by the position of thecollar 39 on the said crank arm 38. Rotation of the crank arm imparts tothe housing 28 an oscillating motion on a slight arcuate plane which istransmitted to the disk H) by virtue of the fulcrum at 33. Thus, therounded bevel a is produced.

It is to be noted that the collar 39 is slotted at 39a. When it isdesired to neutralize the oscillative effect produced by the eccentricrelation between the pivotal points 40 and 21, the collar 33 is slidalong the arm 33 so that the slot will i receive the extended end ofstub shaft 21 and when points 40 and 21 are axially aligned, nooscillating effect is provided.

Mounted on one side of the frame 35, parallel to and movable thereon isa rail 42 on which is movably disposed a weight 43, slidably secured inposition on the rail by a plate 44. The degree of pressure imposed bythe disk on the grinding wheel is increased and decreased byrespectively moving the weight 43 forwardly or rearwardly on the rail62. This also varies the cutting depth and consequently the speed of thesharpening operation.

It frequently happens that disks are encountered with rather deep nicksor indentations in the cutting edges. If the entire Weight of themounting is imposed on the grinding wheel through the disk, the bevelwould of course follow the indentation. To insure against this in thesharpening of out-of-round, irregular or indented disks, the oscillatingunit is rendered inoperative by so moving the collar 39 on arm 38 as tobring pivot points 40 and 21 into axial alinement. When this is done,the shaft 25 is held in stationary relation to the other parts of theassembly. A chain 53 or its equivalent (Figure 1) has one end connectedto the lower end of the upper stand section 6 and its opposite end tothe base N). This chain limits the angle of incline of the stand whenthe latter is tilted and in order that even this may be varied oradjusted, a turnbuckle 5| is incorporated in the length of chain. It isapparent therefore that only the high points of the disk will be engagedby the wheel I4 until such time as these have been ground off to thedepth of the deepest indentation.

The disks I5, usually made of high grade steel are disposed to ringpenetratingly during the grinding operation. In order to mufile ordeaden this noise, a device such as illustrated in Figure 4 is employedand consists of a circular flange a l having on its underside a strip ofleather or other material 45 which bears against the concaved face ofthe disk [5. Radial spokes @6 connect the flange M with the hub 41,through which the shaft 25 passes. A nut 43 is threaded on the shaft 25,as shown in Figure 4 to hold the retaining device on the disk andconsequently secures the latter firmly in place on the sharpenermounting.

Manifestly, the construction as shown and described is capable of somemodification and such modification as may be construed to fall withinthe scope and meaning of the appended claims is also considered to bewithin the spirit and intent of the invention.

What is claimed is:

1. Apparatus for sharpening disks in combination with a grinding wheel,a tiltable, vertically adjustable stand, a frame pivotally attached tothe top of said stand for limited rotation through its major axis, ashaft and shaft housing pivotally suspended by said frame for limitedoscillation in a vertical plane and adapted to hold a disk in operativerelation to said grinding wheel whereby its rotative motion will beimparted to said disk and shaft and means operative through the rotationof said shaft to cause the latter to oscillate on its pivot.

2. A mounting for disks in sharpening comprising in combination with agrinding wheel, a portable base, a sectional stand tiltably supported onsaid base for movement toward and away from said grinding wheel, meansfor axially moving one section of said stand relative to the companionsection to vary the height of said stand, a frame pivoted for rotationin a plane parallel to the axis of said stand, a shaft housing pivotallysuspended by said frame for limited swinging movement in a verticalplane, a shaft in said housing arranged to carry a disk for operativeengagement with said grinding wheel and whereby the motion of the latterwill be transmitted to said disk to rotate said shaft and meansutilizing the rotative motion of said shaft to effect oscillationthereof.

3. A mounting for disks in the process of sharpening in combination witha grinding wheel, a portable base, a stand mounted on said base fortilting movement relative to said grinding wheel, means to effect heightadjustment of said stand, a shaft indirectly supported by said stand andcapable of swinging movement in planes parallel with and transverse tothe axis of said stand, said shaft being arranged to support a disk foroperative engagement with said grinding wheel and whereby the motion ofthe latter will be effective to rotate said disk and shaft and meanseffective through the rotation of said shaft for swinging the latter ina plane parallel to the axis of said stand.

4. A mounting for plow disks in the process of sharpening in combinationwith a grinding wheel, a base, an upright and vertically adjustablestand pivotally disposed on said base for tilting movement toward andaway from said grinding wheel, a shaft having a housing suspended at itsupper end for swinging movement in a plane parallel with thelongitudinal axis of said shaft, means connecting said shaft housing tosaid stand for swinging movement in a plane at right angles to the axisof said stand, said shaft carrying a disk for grinding engagement withsaid grinding Wheel whereby rotation of the latter will be effective torotate said disk and shaft and means in eccentric relation with theloWer end of said shaft to swing the same on its pivot when rotated.

5. Apparatus for supporting a plow disk in operative relation to agrinding wheel in the process of sharpening, a mounting tiltable towardsaid grinding wheel whereby its weight will be imposed through a diskcarried thereby on said grinding wheel, said mounting including a shaftarranged to carry said disk and hold the same in operative relation tosaid grinding wheel and to effect rotation of said disk through rotationof said grinding wheel, a housing for said shaft, means supporting theupper end of said housing for swinging movement, means having eccentricconnection with the lower end of said shaft to impart swinging movementthereto during rotation to arcuately move the point of contact of saiddisk with said grinding wheel.

6. A structure as set forth in claim 5 in which the shaft is likewisemounted for limited adjustment in a plane at right angles to the planein which it is constrained to move in operation.

'7. A structure as described in claim 5 in which the eccentricallyconnected means is comprised of a housing supported at the lower end ofthe disk carrying shaft, a pinion in said housing carried by said shaft,a gear enmeshing said pinion, a crank arm affixed to the shaft of saidgear, a sleeve slidably disposed and securable at adjusted positions onsaid crank arm and an articulated arm connected at one end to saidsleeve and constrained at its other end against other than pivotalmovement in a horizontal plane whereby rotation of said crank arm bysaid shaft will cause said housing and shaft to oscillate.

8. A disk grinding mounting comprising in combination with a grindingwheel, a supporting stand pivoted for tilting movement in a plane atright angles to its longitudinal axis toward and away from said grindingwheel, a disk carrying shaft mounted in a frame suspended from the upperend of said stand for swinging movement toward and away from said standand arranged for adjustment in planes at right angles to the axis ofsaid stand whereby said shaft and a disk carried thereby will receiveits rotation from the rotation of said grinding wheel by contact of saiddisk therewith, means effecting eccentric connection between the lowerend of said shaft and said stand whereby to employ the rotation of saidshaft for effecting swinging movement thereof and means for limiting theangle of inclination of said stand toward said grinding wheel topredetermine the cutting depth of the latter.

9. A disk sharpening mounting comprising in combination with a grindingwheel, a vertically adjustable stand pivoted at its base for inclinationtoward said grinding wheel and capable of horizontal displacement on itspivot, means carried by said stand for supporting a disk in sharpeningrelation to said grinding wheel whereby rotation of the latter willcause rotation of said disk, automatic means for oscillating said diskduring its rotation to arcuately move its point of contact with saidgrinding wheel, means to render said oscillating means ineffective andmeans for limiting the angle of inclination of said stand topredetermine the effective cutting range of said wheel on said disk.

JOSEPH N. FENDER.

